src/doveadm/doveadm-who.c

/* Copyright (c) 2009-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "net.h"
#include "istream.h"
#include "wildcard-match.h"
#include "hash.h"
#include "str.h"
#include "strescape.h"
#include "doveadm.h"
#include "doveadm-print.h"
#include "doveadm-who.h"

#include <stdio.h>
#include <unistd.h>

struct who_user {
    const char *username;
    const char *service;
    ARRAY(struct ip_addr) ips;
    ARRAY(pid_t) pids;
    unsigned int connection_count;
};

static void who_user_ip(const struct who_user *user, struct ip_addr *ip_r)
{
    if (array_count(&user->ips) == 0)
        i_zero(ip_r);
    else {
        const struct ip_addr *ip = array_idx(&user->ips, 0);
        *ip_r = *ip;
    }
}

static unsigned int who_user_hash(const struct who_user *user)
{
    struct ip_addr ip;
    unsigned int hash = str_hash(user->service);

    if (user->username[0] != '\0')
        hash += str_hash(user->username);
    else {
        who_user_ip(user, &ip);
        hash += net_ip_hash(&ip);
    }
    return hash;
}

static int who_user_cmp(const struct who_user *user1,
            const struct who_user *user2)
{
    if (strcmp(user1->username, user2->username) != 0)
        return 1;
    if (strcmp(user1->service, user2->service) != 0)
        return 1;

    if (user1->username[0] == '\0') {
        /* tracking only IP addresses, not usernames */
        struct ip_addr ip1, ip2;

        who_user_ip(user1, &ip1);
        who_user_ip(user2, &ip2);
        return net_ip_cmp(&ip1, &ip2);
    }
    return 0;
}

static bool
who_user_has_ip(const struct who_user *user, const struct ip_addr *ip)
{
    const struct ip_addr *ex_ip;

    array_foreach(&user->ips, ex_ip) {
        if (net_ip_compare(ex_ip, ip))
            return TRUE;
    }
    return FALSE;
}

static int who_parse_line(const char *line, struct who_line *line_r)
{
    const char *const *args = t_strsplit_tabescaped(line);
    const char *ident = args[0];
    const char *pid_str = args[1];
    const char *refcount_str = args[2];
    const char *p, *ip_str;

    i_zero(line_r);

    /* ident = service/ip/username (imap, pop3)
       or      service/username (lmtp) */
    p = strchr(ident, '/');
    if (p == NULL)
        return -1;
    if (str_to_pid(pid_str, &line_r->pid) < 0)
        return -1;
    line_r->service = t_strdup_until(ident, p++);
    line_r->username = strchr(p, '/');
    if (line_r->username == NULL) {
        /* no IP */
        line_r->username = p;
    } else {
        ip_str = t_strdup_until(p, line_r->username++);
        (void)net_addr2ip(ip_str, &line_r->ip);
    }
    if (str_to_uint(refcount_str, &line_r->refcount) < 0)
        return -1;
    return 0;
}

static bool who_user_has_pid(struct who_user *user, pid_t pid)
{
    const pid_t *ex_pid;

    array_foreach(&user->pids, ex_pid) {
        if (*ex_pid == pid)
            return TRUE;
    }
    return FALSE;
}

static void who_aggregate_line(struct who_context *ctx,
                   const struct who_line *line)
{
    struct who_user *user, lookup_user;

    lookup_user.username = line->username;
    lookup_user.service = line->service;

    user = hash_table_lookup(ctx->users, &lookup_user);
    if (user == NULL) {
        user = p_new(ctx->pool, struct who_user, 1);
        user->username = p_strdup(ctx->pool, line->username);
        user->service = p_strdup(ctx->pool, line->service);
        p_array_init(&user->ips, ctx->pool, 3);
        p_array_init(&user->pids, ctx->pool, 8);
        hash_table_insert(ctx->users, user, user);
    }
    user->connection_count += line->refcount;

    if (line->ip.family != 0 && !who_user_has_ip(user, &line->ip))
        array_append(&user->ips, &line->ip, 1);

    if (!who_user_has_pid(user, line->pid))
        array_append(&user->pids, &line->pid, 1);
}

int who_parse_args(struct who_context *ctx, const char *const *masks)
{
    struct ip_addr net_ip;
    unsigned int i, net_bits;

    for (i = 0; masks[i] != NULL; i++) {
        if (net_parse_range(masks[i], &net_ip, &net_bits) == 0) {
            if (ctx->filter.net_bits != 0) {
                i_error("Multiple network masks not supported");
                doveadm_exit_code = EX_USAGE;
                return -1;
            }
            ctx->filter.net_ip = net_ip;
            ctx->filter.net_bits = net_bits;
        } else {
            if (ctx->filter.username != NULL) {
                i_error("Multiple username masks not supported");
                doveadm_exit_code = EX_USAGE;
                return -1;
            }
            ctx->filter.username = masks[i];
        }
    }
    return 0;
}

void who_lookup(struct who_context *ctx, who_callback_t *callback)
{
#define ANVIL_HANDSHAKE "VERSION\tanvil\t1\t0\n"
#define ANVIL_CMD ANVIL_HANDSHAKE"CONNECT-DUMP\n"
    struct istream *input;
    const char *line;
    int fd;

    fd = doveadm_connect(ctx->anvil_path);
    net_set_nonblock(fd, FALSE);
    if (write(fd, ANVIL_CMD, strlen(ANVIL_CMD)) < 0)
        i_fatal("write(%s) failed: %m", ctx->anvil_path);

    input = i_stream_create_fd_autoclose(&fd, (size_t)-1);
    while ((line = i_stream_read_next_line(input)) != NULL) {
        if (*line == '\0')
            break;
        T_BEGIN {
            struct who_line who_line;

            if (who_parse_line(line, &who_line) < 0)
                i_error("Invalid input: %s", line);
            else
                callback(ctx, &who_line);
        } T_END;
    }
    if (input->stream_errno != 0) {
        i_fatal("read(%s) failed: %s", ctx->anvil_path,
            i_stream_get_error(input));
    }

    i_stream_destroy(&input);
}

static bool who_user_filter_match(const struct who_user *user,
                  const struct who_filter *filter)
{
    if (filter->username != NULL) {
        if (!wildcard_match_icase(user->username, filter->username))
            return FALSE;
    }
    if (filter->net_bits > 0) {
        const struct ip_addr *ip;
        bool ret = FALSE;

        array_foreach(&user->ips, ip) {
            if (net_is_in_network(ip, &filter->net_ip,
                          filter->net_bits)) {
                ret = TRUE;
                break;
            }
        }
        if (!ret)
            return FALSE;
    }
    return TRUE;
}

static void who_print_user(const struct who_user *user)
{
    const struct ip_addr *ip;
    const pid_t *pid;
    string_t *str = t_str_new(256);

    doveadm_print(user->username);
    doveadm_print(dec2str(user->connection_count));
    doveadm_print(user->service);

    str_append_c(str, '(');
    array_foreach(&user->pids, pid)
        str_printfa(str, "%ld ", (long)*pid);
    if (str_len(str) > 1)
        str_truncate(str, str_len(str)-1);
    str_append_c(str, ')');
    doveadm_print(str_c(str));

    str_truncate(str, 0);
    str_append_c(str, '(');
    array_foreach(&user->ips, ip)
        str_printfa(str, "%s ", net_ip2addr(ip));
    if (str_len(str) > 1)
        str_truncate(str, str_len(str)-1);
    str_append_c(str, ')');
    doveadm_print(str_c(str));
}

static void who_print(struct who_context *ctx)
{
    struct hash_iterate_context *iter;
    struct who_user *user;

    doveadm_print_header("username", "username", 0);
    doveadm_print_header("connections", "#",
                 DOVEADM_PRINT_HEADER_FLAG_RIGHT_JUSTIFY);
    doveadm_print_header("service", "proto", 0);
    doveadm_print_header("pids", "(pids)", 0);
    doveadm_print_header("ips", "(ips)", 0);

    iter = hash_table_iterate_init(ctx->users);
    while (hash_table_iterate(iter, ctx->users, &user, &user)) {
        if (who_user_filter_match(user, &ctx->filter)) T_BEGIN {
            who_print_user(user);
        } T_END;
    }
    hash_table_iterate_deinit(&iter);
}

bool who_line_filter_match(const struct who_line *line,
               const struct who_filter *filter)
{
    if (filter->username != NULL) {
        if (!wildcard_match_icase(line->username, filter->username))
            return FALSE;
    }
    if (filter->net_bits > 0) {
        if (!net_is_in_network(&line->ip, &filter->net_ip,
                       filter->net_bits))
            return FALSE;
    }
    return TRUE;
}

static void who_print_line(struct who_context *ctx,
               const struct who_line *line)
{
    unsigned int i;

    if (!who_line_filter_match(line, &ctx->filter))
        return;

    for (i = 0; i < line->refcount; i++) T_BEGIN {
        doveadm_print(line->username);
        doveadm_print(line->service);
        doveadm_print(dec2str(line->pid));
        doveadm_print(net_ip2addr(&line->ip));
    } T_END;
}

static void cmd_who(struct doveadm_cmd_context *cctx)
{
    const char *const *masks;
    struct who_context ctx;
    bool separate_connections = FALSE;

    i_zero(&ctx);
    if (!doveadm_cmd_param_str(cctx, "socket-path", &(ctx.anvil_path)))
        ctx.anvil_path = t_strconcat(doveadm_settings->base_dir, "/anvil", NULL);
    (void)doveadm_cmd_param_bool(cctx, "separate-connections", &separate_connections);

    ctx.pool = pool_alloconly_create("who users", 10240);
    hash_table_create(&ctx.users, ctx.pool, 0, who_user_hash, who_user_cmp);

    if (doveadm_cmd_param_array(cctx, "mask", &masks)) {
        if (who_parse_args(&ctx, masks) != 0) {
            hash_table_destroy(&ctx.users);
            pool_unref(&ctx.pool);
            return;
        }
    }

    doveadm_print_init(DOVEADM_PRINT_TYPE_TABLE);
    if (!separate_connections) {
        who_lookup(&ctx, who_aggregate_line);
        who_print(&ctx);
    } else {
        doveadm_print_header("username", "username",
                     DOVEADM_PRINT_HEADER_FLAG_EXPAND);
        doveadm_print_header("service", "proto", 0);
        doveadm_print_header_simple("pid");
        doveadm_print_header_simple("ip");
        who_lookup(&ctx, who_print_line);
    }

    hash_table_destroy(&ctx.users);
    pool_unref(&ctx.pool);
}

struct doveadm_cmd_ver2 doveadm_cmd_who_ver2 = {
    .name = "who",
    .cmd = cmd_who,
    .usage = "[-a <anvil socket path>] [-1] [<user mask>] [<ip/bits>]",
DOVEADM_CMD_PARAMS_START
DOVEADM_CMD_PARAM('a',"socket-path", CMD_PARAM_STR, 0)
DOVEADM_CMD_PARAM('1',"separate-connections", CMD_PARAM_BOOL, 0)
DOVEADM_CMD_PARAM('\0',"mask", CMD_PARAM_ARRAY, CMD_PARAM_FLAG_POSITIONAL)
DOVEADM_CMD_PARAMS_END
};